diff --git a/desktop/src/features/messages/ui/MessageComposerToolbar.tsx b/desktop/src/features/messages/ui/MessageComposerToolbar.tsx
index b47d2fa68..468bf5920 100644
--- a/desktop/src/features/messages/ui/MessageComposerToolbar.tsx
+++ b/desktop/src/features/messages/ui/MessageComposerToolbar.tsx
@@ -20,6 +20,7 @@ import {
   type SpoilerToggleState,
   toggleSpoilerFormatting,
 } from "./FormattingToolbar";
+import { SelectionFormattingTray } from "./SelectionFormattingTray";
 
 /** Spring for enter/exit of button groups — all fire simultaneously. */
 const presenceSpring = {
@@ -98,6 +99,11 @@ export const MessageComposerToolbar = React.memo(
 
     return (
       <div className="mt-2 flex flex-wrap items-center justify-between gap-3">
+        <SelectionFormattingTray
+          disabled={formattingDisabled}
+          editor={editor}
+          onLinkButton={onLinkButton}
+        />
         <div className="flex min-h-10 min-w-0 flex-1 items-center gap-1 py-1">
           {/*
            * AnimatePresence with mode="popLayout" — exiting elements
diff --git a/desktop/src/features/messages/ui/SelectionFormattingTray.tsx b/desktop/src/features/messages/ui/SelectionFormattingTray.tsx
new file mode 100644
index 000000000..e7e29cab3
--- /dev/null
+++ b/desktop/src/features/messages/ui/SelectionFormattingTray.tsx
@@ -0,0 +1,214 @@
+import * as React from "react";
+import { createPortal } from "react-dom";
+import type { Editor } from "@tiptap/react";
+
+import { cn } from "@/shared/lib/cn";
+import { FormattingToolbar } from "./FormattingToolbar";
+
+type SelectionFormattingTrayProps = {
+  editor: Editor | null;
+  disabled?: boolean;
+  onLinkButton?: () => void;
+};
+
+type TrayPosition = {
+  left: number;
+  placement: "top" | "bottom";
+  top: number;
+};
+
+const EDGE_GUTTER = 12;
+const SELECTION_OFFSET = 8;
+const MIN_SPACE_ABOVE = 44;
+
+function clamp(value: number, min: number, max: number): number {
+  return Math.min(Math.max(value, min), max);
+}
+
+function getSelectionRect(editor: Editor): DOMRect | null {
+  const { from, to } = editor.state.selection;
+
+  try {
+    const range = document.createRange();
+    const start = editor.view.domAtPos(from);
+    const end = editor.view.domAtPos(to);
+    range.setStart(start.node, start.offset);
+    range.setEnd(end.node, end.offset);
+
+    const clientRects = Array.from(range.getClientRects()).filter(
+      (rect) => rect.width > 0 || rect.height > 0,
+    );
+    const rect = clientRects[0] ?? range.getBoundingClientRect();
+    range.detach();
+
+    if (rect.width > 0 || rect.height > 0) return rect;
+  } catch {
+    // Fall back to the caret coordinates below.
+  }
+
+  const startCoords = editor.view.coordsAtPos(from);
+  const endCoords = editor.view.coordsAtPos(to);
+  const left = Math.min(startCoords.left, endCoords.left);
+  const right = Math.max(startCoords.right, endCoords.right);
+  const top = Math.min(startCoords.top, endCoords.top);
+  const bottom = Math.max(startCoords.bottom, endCoords.bottom);
+
+  if (right <= left && bottom <= top) return null;
+  return new DOMRect(left, top, Math.max(1, right - left), bottom - top);
+}
+
+function getTrayPosition(
+  editor: Editor,
+  trayWidth: number,
+): TrayPosition | null {
+  const { selection } = editor.state;
+  if (selection.empty || selection.from === selection.to) return null;
+
+  const selectedText = editor.state.doc.textBetween(
+    selection.from,
+    selection.to,
+    "\n",
+    "\n",
+  );
+  if (selectedText.trim().length === 0) return null;
+
+  const rect = getSelectionRect(editor);
+  if (!rect) return null;
+
+  const viewportWidth = window.innerWidth;
+  const viewportHeight = window.innerHeight;
+  const selectionCenter = rect.left + rect.width / 2;
+  const halfTrayWidth = trayWidth / 2;
+  const minLeft = Math.min(
+    viewportWidth - EDGE_GUTTER,
+    EDGE_GUTTER + halfTrayWidth,
+  );
+  const maxLeft = Math.max(
+    EDGE_GUTTER,
+    viewportWidth - EDGE_GUTTER - halfTrayWidth,
+  );
+  const left =
+    minLeft <= maxLeft
+      ? clamp(selectionCenter, minLeft, maxLeft)
+      : viewportWidth / 2;
+  const hasRoomAbove = rect.top >= MIN_SPACE_ABOVE;
+
+  if (hasRoomAbove) {
+    return {
+      left,
+      placement: "top",
+      top: Math.max(EDGE_GUTTER, rect.top - SELECTION_OFFSET),
+    };
+  }
+
+  return {
+    left,
+    placement: "bottom",
+    top: Math.min(viewportHeight - EDGE_GUTTER, rect.bottom + SELECTION_OFFSET),
+  };
+}
+
+export function SelectionFormattingTray({
+  editor,
+  disabled = false,
+  onLinkButton,
+}: SelectionFormattingTrayProps) {
+  const [position, setPosition] = React.useState<TrayPosition | null>(null);
+  const rafRef = React.useRef<number | null>(null);
+  const trayRef = React.useRef<HTMLDivElement | null>(null);
+  const [trayWidth, setTrayWidth] = React.useState(0);
+
+  const updatePosition = React.useCallback(() => {
+    if (!editor || disabled || !editor.isEditable || !editor.isFocused) {
+      setPosition(null);
+      return;
+    }
+    setPosition(getTrayPosition(editor, trayWidth));
+  }, [disabled, editor, trayWidth]);
+
+  const scheduleUpdate = React.useCallback(() => {
+    if (rafRef.current !== null) {
+      window.cancelAnimationFrame(rafRef.current);
+    }
+    rafRef.current = window.requestAnimationFrame(() => {
+      rafRef.current = null;
+      updatePosition();
+    });
+  }, [updatePosition]);
+
+  React.useEffect(() => {
+    if (!editor) {
+      setPosition(null);
+      return;
+    }
+
+    const hide = () => setPosition(null);
+
+    scheduleUpdate();
+    editor.on("selectionUpdate", scheduleUpdate);
+    editor.on("transaction", scheduleUpdate);
+    editor.on("focus", scheduleUpdate);
+    editor.on("blur", hide);
+    window.addEventListener("resize", scheduleUpdate);
+    window.addEventListener("scroll", scheduleUpdate, true);
+
+    return () => {
+      if (rafRef.current !== null) {
+        window.cancelAnimationFrame(rafRef.current);
+        rafRef.current = null;
+      }
+      editor.off("selectionUpdate", scheduleUpdate);
+      editor.off("transaction", scheduleUpdate);
+      editor.off("focus", scheduleUpdate);
+      editor.off("blur", hide);
+      window.removeEventListener("resize", scheduleUpdate);
+      window.removeEventListener("scroll", scheduleUpdate, true);
+    };
+  }, [editor, scheduleUpdate]);
+
+  React.useLayoutEffect(() => {
+    if (!position || !trayRef.current) return;
+
+    const updateTrayWidth = () => {
+      const nextWidth = trayRef.current?.getBoundingClientRect().width ?? 0;
+      setTrayWidth((currentWidth) =>
+        Math.abs(currentWidth - nextWidth) > 1 ? nextWidth : currentWidth,
+      );
+    };
+
+    updateTrayWidth();
+
+    if (typeof ResizeObserver === "undefined") return;
+    const observer = new ResizeObserver(updateTrayWidth);
+    observer.observe(trayRef.current);
+    return () => observer.disconnect();
+  }, [position]);
+
+  if (!position || typeof document === "undefined") return null;
+
+  return createPortal(
+    <div
+      ref={trayRef}
+      className={cn(
+        "fixed z-50 max-w-[calc(100vw-1.5rem)] rounded-lg border border-border/80 bg-popover p-1 text-popover-foreground shadow-lg",
+        position.placement === "top"
+          ? "-translate-x-1/2 -translate-y-full"
+          : "-translate-x-1/2",
+      )}
+      data-testid="selection-formatting-tray"
+      onMouseDown={(event) => event.preventDefault()}
+      role="toolbar"
+      aria-label="Selection formatting"
+      style={{ left: position.left, top: position.top }}
+    >
+      <div className="max-w-full overflow-x-auto">
+        <FormattingToolbar
+          disabled={disabled}
+          editor={editor}
+          onLinkButton={onLinkButton}
+        />
+      </div>
+    </div>,
+    document.body,
+  );
+}
diff --git a/desktop/src/main.tsx b/desktop/src/main.tsx
index 85b14ca09..bbcfa834c 100644
--- a/desktop/src/main.tsx
+++ b/desktop/src/main.tsx
@@ -18,8 +18,7 @@ type E2eWindow = Window & {
 
 const E2E_DEFAULT_PUBKEY = "deadbeef".repeat(8);
 const E2E_WORKSPACE_ID = "e2e-default-workspace";
-const ONBOARDING_COMPLETION_STORAGE_KEY_PREFIX =
-  "sprout-onboarding-complete.v1:";
+const ONBOARDING_COMPLETION_STORAGE_KEY_PREFIX = "buzz-onboarding-complete.v1:";
 
 function configureDevE2eBridgeFromUrl() {
   if (!import.meta.env.DEV) {
@@ -40,8 +39,8 @@ function configureDevE2eBridgeFromUrl() {
     name: "E2E Test",
     relayUrl: "ws://localhost:3000",
   };
-  window.localStorage.setItem("sprout-workspaces", JSON.stringify([workspace]));
-  window.localStorage.setItem("sprout-active-workspace-id", E2E_WORKSPACE_ID);
+  window.localStorage.setItem("buzz-workspaces", JSON.stringify([workspace]));
+  window.localStorage.setItem("buzz-active-workspace-id", E2E_WORKSPACE_ID);
   window.localStorage.setItem(
     `${ONBOARDING_COMPLETION_STORAGE_KEY_PREFIX}${E2E_DEFAULT_PUBKEY}`,
     "true",